Resilient slat-seat chair



Dec. 29, 1953 P. N. HOWARD 2,664,149

RESILIENT SLAT-SEAT CHAIR Filed Aug. 15, 1950 IN VEN TOR.

/ AUL N. HOWARD ATTORNEYS Patented Dec. 29, 1953 RESILIENT SLAT-SEATCHAIR Paul N. Howard, Kent, Wash, assignor to Howard Manufacturing 00.,Kent, Wash., a partnership Application August 15, 1950, Serial No.179,436

' 8 Claims.

This invention concerns slat chairs, that is to say, chairs of the typefrequently employed on lawns and porches, in which the seat, andgenerally the back as well, is formed primarily of slats of wood. Suchslats, being thin, have inherent flexibility, but can be easilyoverstressed by concentration of force to the point of breakmg.

Because of the danger of over-stressing and breaking individual slats,such chair seats are generally so constructed that the flexibility oithe slats is greatly limited, and to that end the slats are quiterigidly supported. While the slats can thus be made relatively thin,with a consequent saving of the stock of which they are made,nevertheless such seats, although in general comfortable, lack anyfeeling of yieldability or flexibility because of this rigidity ofconstruction, and to that extent are somewhat less comfortable than isdesirable.

It is a primary object of the present invention to provide a slat chairof suitable construction, wherein, in the seat at least, advantage istaken of the flexibility inherent in the thin slats ordi narily used, tomake the seat somewhat flexible and springy, and yet that flexibility issufiiciently limited that there is no danger of overstressing the slatsto the point of breaking them. Thus, and by the construction which Willbe described, such slat chairs, without greatly adding to their cost,and in particular without the employment of thicker slats or ofappreciably more good grade lumber than in the ordinary chair of thesame general type, are rendered somewhat yielding or springy in theseat, and to that extent are made appreciably more comfortable anddesirable.

lhe invention will be described in conjunction with a folding chair, butit will be understood that the same principles are applicable to thechair whether or not it is foldable, and likewise to a settee or abench, and is not limited to a chair for single occupancy, but can beapplied to an elongated seat or" such type as has been mentioned. It isintended to include any such seat wherever herein the term chair isused.

With the objects above in mind, and others as will appear as thisspecification progresses, the present invention comprises the novelchair and the novel combination and arrangement of the parts thereof,particularly in the seat portion, as is shown in the accompanyingdrawings, as will be described in this specification, and as will bemore particularly pointed out in the claims which terminate the same.

As has been explained above, the present inin unfolded or operativeposition.

side bars vention is not limited to a chair in the strict sense of theword, and is not to be limited to the precise forms and arrangementsherein shown and dw scribed, otherwise than as is set forth in theclaims.

Figure 1 is an isometric sectional view through such a chair on avertical plane from i'ront to rear, the line of section being indicatedat l-i in Figure 2, and Figure 2 is a transverse sectional view throughthe seat portion or such a chair on a plane indicated generally by theline 2-2 in Figure 1.

The supporting structure of the chair in general comprises the forwardlegs 9, the rear legs til, the side irame elements iii of the baci;joined by the transverse slats 92, and the side arms Since the chairillustrated is a folding chair, these various elements are pivotably andfold ably connected together in known l2t211i0i1, the precise manner orsuch connection being im material to the present invention, whichconcerns primarily the seat. It will be clear that the legs atthe'opposite sides will be connected across, by the transverse struts ccconnecting the ior- Ward legs 9, and a transversestrut 95 connects therearlegs 96. As is customary in such folding chairs, a third transversestrut or round it connects across the frame members ill of the back andrests on the upper edge or the rear legs in a known manner, to supportthe same However, the strut 8 might connect equally well the legs orsupporting portion or the cnalr, so rar as concerns its runctionlng inthe present invention, in which it has an important part.

The seat, as is customary, is made up of thin transverse slats generallydesignated by the numeral l, butindividually designated by varioussunixes, as Ia, lb, lo and let, the distinction between which willshortly appear. lneseslats rest at their ends upon and are secured tosupported by iorwarclly and rearwardiydirected The upper edges or theseside care may be straight, or they may be contoured, the latterconrormation being prererred.

These slats are made of wood which is inherently flexible, but which canbecome overstressed and will break upon too great ccncentration ofweight and consequent excessive fiexure. It is-evident that suchover-stressing and breaking could be prevented if they were alwayssolidly supported in their central portion, intermediate their ends, andyet if so supported they would be robbed of their flexibility. in oroerto-aiiord some degree of flexibility, and yet to insure limiting theirflexing to a value less than sufficient to over-stress any individualslat, or all of them, I provide a central support of a peculiar kind, inwhich the ultimate support is the transverse strut 8, between which andcertain of the centrally disposed slats lc there is provision for lostmotion in a vertical sense, but for limitation of their flexibility andthis consequent motion to a value such that the slats cannot becomeover-stressed. In the construction illustrated there is such lost motionprovided at two points, but lost motion at either one of such pointswould to a limited degree afford a realization of the advantages of thisinvention. It is preferred that lost motion be provided at both suchpoints, for each complements the effect of the other, and serves todistribute the stresses to slats not otherwise so heavily stressed, ifstressed at all in use, and affords the springy flexibility of theentire group of seat slats to the yieldability of the seat, whereverstress is concentrated thereon.

An intermediate bar 3, similar in contour and disposition to the sidebars 2, is located intermediate the two latter, underlying all the slatsl. ts forward end is suitably supported, the support in the illustratedform being constituted by the screw connection at 30 to the forwardslats la and lb. Its rear end is similarly supported by its connectionat 3| to the rear slat Id. Between the slats lb and Id are disposed theseveral slats lo, and the contour of the upper edge 32 of theintermediate bar 3 is such that in the normal unstressed position of theslats lc, these slats are individually spaced above the edge 32 by adefinite distance, so that the slats lc, when depressed by the weight ofan occupant sitting upon the seat, will yield downwardly, as shown indash lines in Figure 1, or as shown in full lines in Figure 2, untilthey contact the upper edge 32 of the intermediate bar 3. Upon suchcontact their downward movement is limited or halted, with an exceptionwhich is about to be disclosed.

The rear end of the intermediate bar 3 is supported at 3| by the rearslat Id normally at a definite spacing above the transverse strut 8.Since the slat ld is itself flexible, when the weight of the occupant,acting through the depressed slats lc on the bar 3, tends to press thebar downwardly, that bar will in effect hinge about its somewhat morerigidly supported forward end, and its rear end will move downwardly,again as shown in dash lines in Figure 1, or as shown in full lines inFigure 2, flexing and pulling downwardly the rear slat ld, until the bar3 engages and is supported by the fixedly positioned and relativelyrigid strut 8, which limits the downward movement of the bar 3 and henceof the slats which are pressing the latter downward or are being pulleddownwardly. The spacings between the slats lo and the upper edge of thebar 3 and between the rear end of the bar 3 and the strut 8 are socalculated as not to overstress the slats of the seat.

It will be noted that the slats lb, to which the intermediate bar 3 issecured, lie generally in a plane normal to the gravity component of theweight of an occupant of the chair, whereas the slat la, forwardthereof, is disposed at a definite angle to such gravity component. Inthis manher the relatively angularly disposed slat la tends to stiffenthe slat or slats lb, and thereby to effect a hinge action at theforward end of the bar 3 rather than to permit appreciable downwarddeflection of the forward slats, for these have no other support. Thebars la and lb mutually stiffen one another and limit yet do not whollydestroy their mutual flexibility, and thereby protect one another fromover-stressing, notwithstanding that no inconsiderable portion of theweight of the occupant is concentrated in the vicinity of these forwardslats. This affords a simple construction and does not require apositive transverse strut or support beneath the forward edge of the bar3, and the rear support at 8 is required in any event for the propersupport of the foldable back. The construction adopted is therefore asimple and economical one and requires no additional material other thanthat included in the bar 3, and but little additional labor, being onlythat required for secureinent at 30 and 3l of certain slats to theintermediate bar 3.

The resilient stiffness afforded by the forward slats, and theresilience of the rear slat ld, serve to restore the bar 3 to its upperunstressed posi tion when the occupant arises. In like fashion theinherent resilience of the slats lc restores them to their upper orunstressed position under like circumstances.

In this specification emphasis has been placed on the use and effect ofthe use of wooden slats. Slats of wood are very widely and commonlyused, and such a construction as has been de scribed is admirablyadapted to the continued use of such slats of wood and the employment tothe best advantage of their limited flexibility but tendency to breakunder concentrated excessive stress. Nevertheless, some chairs of thistype are made of plastic material, and the plastic chairs have certainadvantages, particularly in extremely dry climates. Accordingly, it isnot intended to limit the invention to chairs wherein the slats, or forthat matter the frame members, are of wood only, but to include in thatterm equivalent materials such as plastic.

I claim as my invention:

1. A chair seat and seat supporting member comprising, in combination,two rigid side bars disposed at the opposite sides of the seat, directedforwardly and rearwardly, a plurality of resilient slats, each ofmaterial which has limited flexibility before it becomes overstressed,each disposed generaliy parallel to the others, in transversedisposition from front to rear, and each resting upon and rigidlysecured to the side bars at its opposite ends, a third rigid barextending forwardly and rearwardly beneath the slats, intermediate theirends, means to suspend said third bar from certain of said slats, andthereby to support said third bar when the slats are unstressed, and asupport spaced beneath said third bar and mounted on said seatsupporting member to limit its downward movement accompanying downwardnovement of the slats when the slats are flexed, and to alford supportfor the so-stressed slats, to restrict their stressing within safe1Lmits.

2. A chair seat in claim 1, wherein the susending means for the thirdbar are engaged between the latter and slats at front and at rear of theseat, only, leaving the third bar unsuspended from the interveningslats, said third bar being recessed at its upper edge to lie below suchintervening slats when the latter are unstressed, but to be engaged byand to limit stressing of such intervening slats, when the latter areflexed downwardly, within safe limits.

3. A chair seat as in claim 2, wherein the suspending means for thethird bar are engaged between the latter and several slats at front ofthe seat, and with a lesser number of slats at rear of the seat, andwherein the support limiting downward movement of said third bar islocated beneath the rear end, only, of said third bar, to limit itsdownward movement and accompanying fiexure of such slats as suspend therear end of the third bar. 7

4. A chair seat as in claim 1, wherein a transverse strut locatedbeneath the rear end of the third bar, and spaced therefrom when theslats are unstressed, constitutes the sole support engageable by saidthird bar to limit its downward movement and flexure of the slats, whenthe latter are stressed.

5. A chair seat having two fixedly positioned side bars directedforwardly and rearwardly at its respectively opposite sides, a third barsimilarly directed but disposed intermediate the two side bars, atransverse strut fixedly positioned a definite distance beneath thenormal unstressed position of the rear end of said intermediate bar, andconstituting a limit stop for its downward movement, and transverseslats extending between and secured to the two side bars and overlyingthe intermediate bar, the forward end of the intermediate bar beingsupportingly secured to at least one slat adjacent the forward edge ofthe seat, and the slats being of material which is limitedly flexiblebefore becoming overstressed, and the spacing of the strut beneath therear end of the intermediate bar being sufliciently great to enableflexing of the slats, but sufficiently slight to limit flexing of theslats to a value less than is required to overstress the slats.

6. A chair seat as in claim 5, wherein the upper edge of theintermediate bar, between its ends,

is spaced beneath the normal unstressed position of certain slatsintermediate the forward and rearward slats, to permit flexing of thesame and to limit their downward flexing to a value less than sufficientto overstress such slats.

7. A- chair seat as in claim 5, wherein the forward end of theintermediate bar is additionally supportingly secured to more than theone slat at the forward edge of the seat, for mutual support of theseveral such slats from the intermediate bar, and of that barsubstantially rigidly from the several such slats.

8. A chair seat as in claim 7, characterized in that two forward slats,whereto the intermediate bar is secured, are disposed one in a planegenerally normal to the weight of an occupant, and the other, being theforward slat of the two, in a plane at an angle to the plane of thefirst such slat, for mutual stiffening of the support for the forwardend of the intermediate bar.

PAUL N. HOWARD.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 124,507 Owen et a1 Mar. 12, 1872 1,962,464 Richtsteig June 12,1934 2,090,971 Whittington et al. Aug. 24, 1937 2,106,066 Sadgrove Jan.18, 1938 2,125,773 Drabenstott Aug. 2, 1938 2,329,572 Young Sept. 14,1943 2,371,825 Kalpakoif Mar. 20, 1945 FOREIGN PATENTS Number CountryDate 221,202 Great Britain Nov. 13, 1924 801,976 France May 30, 1936

